1. Field of the Invention
The invention is in the field of the structure and fabrication of honeycomb panel as a rigid, light weight structural element.
2. Brief Description of the Background Art
Honeycomb panel is a structural element widely used for applications requiring the combination of rigidity and light weight. However, fabrication of honeycomb panel can be quite complex and expensive. The panel consists of side sheets bonded to a honeycomb core, consisting of many strips of sheet material. The strips are bonded to form an array of, typically, hexagonal shapes. One common method of bonding the strips to one another is spot welding. However, this is a complex repetitive operation that limits the thickness of panel that can be produced, particularly for smaller hexagonal cells.
Another limitation of many prior art processes is the jigging and fixturing needed to hold the strips in position and registration for bonding. Prior Art Techniques that have addressed some of these problems have introduced other limitations in, for example, the achievable size of the panel produced. For example, U.S. Pat. No. 2,910,153 shows a honeycomb panel whose core consists of a series of flanged strips, fitting together at the flanged edge of each strip. While providing automatic registration and being disclosed as interlocking, these strips must be held together prior to bonding and, for thicker panels, the strips can separate at the center, possibly degrading the panel's structural strength. U.S. Pat. No. 3,200,489 discloses a method that produces uniform bonding through the thickness of the panel, but does not produce automatic registration of the component sheets. Without accurate jigging and fixturing, this could result in nonuniformities in the core and weak points in the panel. The herein disclosed invention solves these problems and others in a way that removes many of the limitations inherent in prior art processes.